I think this is the major issue, especially in procedural specialties. IP stuff outside of EBUS (stents and cryo and s**t), EMR and other advanced endoscopy, TAVR and peripheral vascular...all that needs more training, there's just no way around it. And you need the base (bronch, EGD, cath) experience to even get to the advanced stuff. So I suspect that these sub-specialties will continue to have increased training requirements.
And the hell of it is, one could easily argue that PCCM, GI and Cards are specialties that require an extremely solid IM base in order to do well. I think the analogies to the integrated surgery programs is a flawed one. If you're doing an integrated vascular program, you can just focus on the tubes with the blood in them and forget the rest. Integrated CT surg? Anything above the clavicle and below the diaphragm doesn't exist. Integrated plastics? If you can't see it in the exam room, it doesn't matter. Advanced training in cards, GI and PCCM doesn't have that luxury.